Environment Optimization for Crowd Evacuation

Robust Space-Time Footsteps for Agent-Based SteeringBy Glen Berseth1, Mubbasir Kapadia2, Petros Faloutsos3

University of British Columbia1, Rutgers University2, York University3 Picture

Have 15 minutes for talk? 12 minutes for presentation 3 minutes for question?1Interface between steering and motion synthesisSimple Sliding DiskPositionVelocityNo information about limbs

DiscsTo large, bad crowd packingTwo small, limb collisions

2GoalsBetter interface between steering and motion synthesisSufficiently detailed information for motion synthesisEfficient space-time planningHeterogeneous agentsBetter qualitative performance

3Contributions:Geometric pruning of search space Search uses randomized step directions and timesNew types of footsteps (In-place turning)Benefits:5x performance increaseImproved stability and local minima avoidanceElimination of certain deadlocking configurations4Related WorkFootstep-based steeringRobotics [Lots]Animation [van Basten and Egges 2010, Singh et al. 2011]The work that is related to this research5Example

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Footstep State Space

{Com Position, COM velocity, current foot position, current foot orientation, current foot}7Motion PlannerNear-optimal finite horizon best first searchCost function:Maintaining certain speedChanging momentumHeuristic estimate:Estimates the number of steps to the goal and then computes the associated energy cost

Regions are important, dont use goal location8Successor State GenerationAd-hoc, discreteRandomized, continuous

Possible successor states for right foot

Ad-hoc methods are susceptible to complex configurations9Dynamic Collision Model

Dynamic collision model is complex10Geometric Validation

Initial placementEnd of finite horizon plan11Examples

Analysis metrics:Quality:Complete:Reached target locationSolved: Reached target location without collisionEfficiency:SimTime: Time to finish simulationAnalysis

99.7% completion[Singh et al. 11]Describe metrics14Questions?Robust Space-Time Footsteps for Agent-Based SteeringBy Glen Berseth1, Mubbasir Kapadia2, Petros Faloutsos3

University of British Columbia1, Rutgers University2, York University3

Footstep Model

Sliding Disk IssuesHas fixed collision boundariesProvides no contact pointsFew locomotionconstraints (turning radius, sharp changesin direction)No space time planning

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